But the device is actually part of a sound amplification system that the Hamilton Heights Primary teacher uses to make her voice heard well throughout her pre-first-grade classroom.

The system, which is designed to help children with hearing loss or attention disorders, is a portable one on loan to the school from a company named Phonic Ear. Speech Pathologist Sue Rider is hoping to secure grants to have the system installed permanently in two classrooms.

Murray, who has had the system for only a few days, says she already notices a difference with her students.

"When I speak, no matter where I am in the room, they're listening," she said. "It engages them and helps them focus by filtering out background noise."

The portable system she is using during a 45-day trial period consists of the headset, a handheld microphone for student use and a speaker.

"I can't believe the sound that comes out of that 4-foot tower," Murray said.

If a permanent system is installed, four speakers mounted in the ceiling would rain sound down into the classroom, she said. Each unit costs $1,495.

"It's such a simple concept," Murray said. And it could be very effective for her students, many of whom suffer from chronic ear infections.

Rider said when the set first was tested in Murray's classroom, the eyes of one student at the back of the room lit up.

"Mrs. Murray, I can hear every word you said," he said.

Rider said she would like to see the device installed in Murray's class, which helps students who need an extra year of instruction before beginning first-grade. The device also could be installed in an extended kindergarten class that serves at-risk students.

Rider said research has shown that the system improves test scores and reduces teacher fatigue, because teachers don't have to raise their voice to be heard all over the room or repeat directions as often.

Murray said she has noticed that she has been speaking softer than her normal "teacher" voice.

"We're talking all day," she said. "If you're not expending all that extra energy, it may help."

The system already is helping her students, though. When asked if he could tell a difference in his teacher's voice with the system, Zacharaya Stevens said it took a little getting used to, but he finds it helpful.

"It was louder, and we can hear her much better," Stevens said. "It kind of looked scary for the first part, but I got used to it, and I didn't even notice it was on."

By Beth Shively